1. Field of the Invention
The present invention relates to dense composite materials, methods for manufacturing such materials, joined bodies, and members for semiconductor manufacturing apparatuses.
2. Description of the Related Art
An electrostatic chuck, which is heated to high temperatures during semiconductor processes, has a cooling plate joined thereto for heat radiation. In this case, the material used for the electrostatic chuck may be aluminum nitride, the material used for the cooling plate may be aluminum, and the joining material used may be a resin. Aluminum nitride and aluminum have an extremely large difference in linear thermal expansion coefficient. For example, aluminum nitride has a linear thermal expansion coefficient of 5.0 ppm/K (RT-800° C., “Physics of Ceramics”, Uchida Rokakuho Publishing Co., Ltd.), whereas aluminum has a linear thermal expansion coefficient of 31.1 ppm/K (RT-800° C., “Thermophysical Properties Handbook New Edition”, edited by Japan Society of Thermophysical Properties). Such an electrostatic chuck uses a soft resin as the joining material so that the stress due to the difference in linear thermal expansion coefficient can be relieved.